May 24, 2005
Experts Tout Breakthrough in Wolf Breeding
ST. LOUIS -- Two artificially inseminated Mexican gray wolves recently gave birth to a combined eight living pups at a research site founded by late naturalist Marlin Perkins, marking perhaps the first time the non-surgical technique has worked with endangered wolves.
Wildlife officials cheered word of the newcomers to the St. Louis-area Wild Canid Survival and Research Center - the world's largest holder and breeder of Mexican gray wolves - as proof of the technology's usefulness in rebuilding the population of the animals.Among other things, the "phenomenal" breakthrough someday may enable noninvasive fertilization of female wolves in the wild, no longer requiring them to be caged or disruptively brought in for insemination, said Kim Scott, the center's assistant director.
"This could have huge implications for future genetic management of Mexican wolves," said Colleen Buchanan of the U.S. Fish and Wildlife Service.
Surgical inseminations have been done previously with endangered red wolves, though the noninvasive technique now appears to work with the Mexican wolves.
Of the nine pups born - six on May 4, three on April 30 - eight still were alive Monday and "are all doing wonderful, doing great," growing and increasingly vocalizing, Scott said.
The pups born April 30 are being fed by bottle, given the mother's inexplicable failure or refusal to nurse them, Scott said.
"She's not a real good mom, for reasons we can't put our finger on," Scott said. "She just has some history of unusual behavior.
Ragnar Thomassen of the University of Oslo Veterinary School, a Norwegian scientist who had perfected a non-surgical, artificial insemination technique for foxes and domestic dogs, was brought in to perform the technique on Mexican wolves. It involves threading a flexible catheter through the female's cervix so it reaches into the uterus. There, the semen from a male wolf considered to be genetically important to the health of the species is injected.
The Saint Louis Zoo's reproductive research department has worked with the center's Mexican gray wolves since 1990 and collaborated in the feat.
Dr. Cheryl Asa, research director for the zoo, said the technique doesn't require anesthesia for domestic dogs. The wolves, however, were anesthetized because as wild animals, they can't be handled. Artificial insemination is necessary to manage the genetic health of these monogamous animals, Asa said.
The average litter size is four to six, according to the center, located on five dozen isolated, wooded acres near Eureka, about 20 miles southwest of St. Louis and popularly known as the Wolf Sanctuary.
The center is part of a federal program to restore the Mexican gray wolf, the rarest and most genetically distinct subspecies of gray wolf in North America.
As part of the program, wolves born at the research center may stay, eventually be moved to another captive site or be freed into the wild to their species' natural range in the American Southwest.
In the 1970s, the wolves disappeared completely from the U.S., and beginning in 1998 they were reintroduced in the Southwest. There now are roughly 60 of the wolves in Arizona and New Mexico, another 200 or so in captivity, according to Susan Lyndaker Lindsey, chief of the canid center.
The center was founded in 1971 by Perkins - a southwest Missouri native - and has programs to protect other canids, including the endangered red wolf. The center is the nation's leader in breeding eventually released Mexican wolves, having birthed 147 pups.
"Today, all packs of wild Mexican grays trace their roots back to our center," Lindsey said.
Though opponents have pushed to block the wolves' reintroduction into the wild, citing the animals' preying on livestock or pets, the target of a federal program is to get about 200 Mexican gray wolves back in the wild.
Lindsey said the Mexican gray wolves help restore a natural balance to the areas where they live in the wild, increase tourism and naturally tend to stay away from people.
On the Net:
Wild Canid Center: http://www.wolfsanctuary.org/
St. Louis Zoo: http://www.stlzoo.org/